﻿using MySql.Data.MySqlClient;
using System;
using System.Collections;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;

namespace znsd.Utility
{
    /// <summary>
    /// 数据访问抽象基础类
    /// </summary>
   public  class SQLHelper
    {
            //数据库连接字符串(web.config来配置)，可以动态更改connectionString支持多数据库.        
           // public static string connectionString = "server=127.0.0.1;database=sss;uid=root;pwd=123456";
       static string connectionString = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;
        public SQLHelper()
            {
            Console.WriteLine(connectionString + "数据库连接串");
            }

            #region 公用方法
            /// <summary>
            /// 得到手动创建Id最大值
            /// </summary>
            /// <param name="FieldName"></param>
            /// <param name="TableName"></param>
            /// <returns></returns>
            public static int GetMaxID(string FieldName, string TableName)
            {
                string strsql = "select max(" + FieldName + ")+1 from " + TableName;
                object obj = GetSingle(strsql);
                if (obj == null)
                {
                    return 1;
                }
                else
                {
                    return int.Parse(obj.ToString());
                }
            }



            /// <summary>
            /// 是否存在
            /// </summary>
            /// <param name="strSql"></param>
            /// <returns></returns>
            public static bool Exists(string strSql)
            {
                object obj = GetSingle(strSql);
                int cmdresult;
                if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                {
                    cmdresult = 0;
                }
                else
                {
                    cmdresult = int.Parse(obj.ToString());
                }
                if (cmdresult == 0)
                {
                    return false;
                }
                else
                {
                    return true;
                }
            }





            /// <summary>
            /// 是否存在（基于MySqlParameter）
            /// </summary>
            /// <param name="strSql"></param>
            /// <param name="cmdParms"></param>
            /// <returns></returns>
            public static bool Exists(string strSql, params MySqlParameter[] cmdParms)
            {
                object obj = GetSingle(strSql, cmdParms);
                int cmdresult;
                if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                {
                    cmdresult = 0;
                }
                else
                {
                    cmdresult = int.Parse(obj.ToString());
                }
                if (cmdresult == 0)
                {
                    return false;
                }
                else
                {
                    return true;
                }
            }
            #endregion

            #region  执行简单SQL语句




            /// <summary>
            /// 执行SQL语句，返回影响的记录数
            /// </summary>
            /// <param name="SQLString">insert delete update SQL语句</param>
            /// <returns>影响的记录数</returns>
            public static int ExecuteSql(string SQLString)
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    using (MySqlCommand cmd = new MySqlCommand(SQLString, connection))
                    {
                        try
                        {
                            connection.Open();
                            int rows = cmd.ExecuteNonQuery();
                            return rows;
                        }
                        catch (MySql.Data.MySqlClient.MySqlException e)
                        {
                            connection.Close();
                            throw e;
                        }
                    }
                }
            }

            public static int ExecuteSqlByTime(string SQLString, int Times)
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    using (MySqlCommand cmd = new MySqlCommand(SQLString, connection))
                    {
                        try
                        {
                            connection.Open();
                            cmd.CommandTimeout = Times;
                            int rows = cmd.ExecuteNonQuery();
                            return rows;
                        }
                        catch (MySql.Data.MySqlClient.MySqlException e)
                        {
                            connection.Close();
                            throw e;
                        }
                    }
                }
            }


            /// <summary>
            /// 执行多条SQL语句，实现数据库事务。
            /// </summary>
            /// <param name="SQLStringList">多条SQL语句</param>        
            public static int ExecuteSqlTran(List<String> SQLStringList)
            {
                using (MySqlConnection conn = new MySqlConnection(connectionString))
                {
                    conn.Open();
                    MySqlCommand cmd = new MySqlCommand();
                    cmd.Connection = conn;
                    MySqlTransaction tx = conn.BeginTransaction();
                    cmd.Transaction = tx;
                    try
                    {
                        int count = 0;
                        for (int n = 0; n < SQLStringList.Count; n++)
                        {
                            string strsql = SQLStringList[n];
                            if (strsql.Trim().Length > 1)
                            {
                                cmd.CommandText = strsql;
                                count += cmd.ExecuteNonQuery();
                            }
                        }
                        tx.Commit();
                        return count;
                    }
                    catch
                    {
                        tx.Rollback();
                        return 0;
                    }
                }
            }




            /// <summary>
            /// 执行带一个存储过程参数的的SQL语句。
            /// </summary>
            /// <param name="SQLString">SQL语句</param>
            /// <param name="content">参数内容,比如一个字段是格式复杂的文章，有特殊符号，可以通过这个方式添加</param>
            /// <returns>影响的记录数</returns>
            public static int ExecuteSql(string SQLString, string content)
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    MySqlCommand cmd = new MySqlCommand(SQLString, connection);
                    MySql.Data.MySqlClient.MySqlParameter myParameter = new MySql.Data.MySqlClient.MySqlParameter("@content", SqlDbType.NText);
                    myParameter.Value = content;
                    cmd.Parameters.Add(myParameter);
                    try
                    {
                        connection.Open();
                        int rows = cmd.ExecuteNonQuery();
                        return rows;
                    }
                    catch (MySql.Data.MySqlClient.MySqlException e)
                    {
                        throw e;
                    }
                    finally
                    {
                        cmd.Dispose();
                        connection.Close();
                    }
                }
            }




            /// <summary>
            /// 执行带一个存储过程参数的的SQL语句。
            /// </summary>
            /// <param name="SQLString">SQL语句</param>
            /// <param name="content">参数内容,比如一个字段是格式复杂的文章，有特殊符号，可以通过这个方式添加</param>
            /// <returns>影响的记录数</returns>
            public static object ExecuteSqlGet(string SQLString, string content)
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    MySqlCommand cmd = new MySqlCommand(SQLString, connection);
                    MySql.Data.MySqlClient.MySqlParameter myParameter = new MySql.Data.MySqlClient.MySqlParameter("@content", SqlDbType.NText);
                    myParameter.Value = content;
                    cmd.Parameters.Add(myParameter);
                    try
                    {
                        connection.Open();
                        object obj = cmd.ExecuteScalar();
                        if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                        {
                            return null;
                        }
                        else
                        {
                            return obj;
                        }
                    }
                    catch (MySql.Data.MySqlClient.MySqlException e)
                    {
                        throw e;
                    }
                    finally
                    {
                        cmd.Dispose();
                        connection.Close();
                    }
                }
            }




            /// <summary>
            /// 向数据库里插入图像格式的字段(和上面情况类似的另一种实例)
            /// </summary>
            /// <param name="strSQL">SQL语句</param>
            /// <param name="fs">图像字节,数据库的字段类型为image的情况</param>
            /// <returns>影响的记录数</returns>
            public static int ExecuteSqlInsertImg(string strSQL, byte[] fs)
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    MySqlCommand cmd = new MySqlCommand(strSQL, connection);
                    MySql.Data.MySqlClient.MySqlParameter myParameter = new MySql.Data.MySqlClient.MySqlParameter("@fs", SqlDbType.Image);
                    myParameter.Value = fs;
                    cmd.Parameters.Add(myParameter);
                    try
                    {
                        connection.Open();
                        int rows = cmd.ExecuteNonQuery();
                        return rows;
                    }
                    catch (MySql.Data.MySqlClient.MySqlException e)
                    {
                        throw e;
                    }
                    finally
                    {
                        cmd.Dispose();
                        connection.Close();
                    }
                }
            }




            /// <summary>
            /// 执行一条计算查询结果语句，返回查询结果（object）。
            /// </summary>
            /// <param name="SQLString">计算查询结果语句</param>
            /// <returns>查询结果（object）</returns>
            public static object GetSingle(string SQLString)
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    using (MySqlCommand cmd = new MySqlCommand(SQLString, connection))
                    {
                        try
                        {
                            connection.Open();
                            object obj = cmd.ExecuteScalar();
                            if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                            {
                                return null;
                            }
                            else
                            {
                                return obj;
                            }
                        }
                        catch (MySql.Data.MySqlClient.MySqlException e)
                        {
                            connection.Close();
                            throw e;
                        }
                    }
                }
            }
            public static object GetSingle(string SQLString, int Times)
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    using (MySqlCommand cmd = new MySqlCommand(SQLString, connection))
                    {
                        try
                        {
                            connection.Open();
                            cmd.CommandTimeout = Times;
                            object obj = cmd.ExecuteScalar();
                            if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                            {
                                return null;
                            }
                            else
                            {
                                return obj;
                            }
                        }
                        catch (MySql.Data.MySqlClient.MySqlException e)
                        {
                            connection.Close();
                            throw e;
                        }
                    }
                }
            }



            /// <summary>
            /// 执行查询语句，返回MySqlDataReader ( 注意：调用该方法后，一定要对MySqlDataReader进行Close )
            /// </summary>
            /// <param name="strSQL">查询语句</param>
            /// <returns>MySqlDataReader</returns>
            public static MySqlDataReader ExecuteReader(string strSQL)
            {
                MySqlConnection connection = new MySqlConnection(connectionString);
                MySqlCommand cmd = new MySqlCommand(strSQL, connection);
                try
                {
                    connection.Open();
                    MySqlDataReader myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                    return myReader;
                }
                catch (MySql.Data.MySqlClient.MySqlException e)
                {
                    throw e;
                }

            }




            /// <summary>
            /// 执行查询语句，返回DataSet
            /// </summary>
            /// <param name="SQLString">查询语句</param>
            /// <returns>DataSet</returns>
            public static DataSet Query(string SQLString)
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    DataSet ds = new DataSet();
                    try
                    {
                        connection.Open();
                        MySqlDataAdapter command = new MySqlDataAdapter(SQLString, connection);
                        command.Fill(ds, "ds");
                    }
                    catch (MySql.Data.MySqlClient.MySqlException ex)
                    {
                        throw new Exception(ex.Message);
                    }
                    return ds;
                }
            }
            public static DataSet Query(string SQLString, int Times)
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    DataSet ds = new DataSet();
                    try
                    {
                        connection.Open();
                        MySqlDataAdapter command = new MySqlDataAdapter(SQLString, connection);
                        command.SelectCommand.CommandTimeout = Times;
                        command.Fill(ds, "ds");
                    }
                    catch (MySql.Data.MySqlClient.MySqlException ex)
                    {
                        throw new Exception(ex.Message);
                    }
                    return ds;
                }
            }



            #endregion

            #region 执行带参数的SQL语句

            /// <summary>
            /// 执行SQL语句，返回影响的记录数
            /// </summary>
            /// <param name="SQLString">SQL语句</param>
            /// <returns>影响的记录数</returns>
            public static int ExecuteSql(string SQLString, params MySqlParameter[] cmdParms)
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    using (MySqlCommand cmd = new MySqlCommand())
                    {
                        try
                        {
                            PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                            int rows = cmd.ExecuteNonQuery();
                            cmd.Parameters.Clear();
                            return rows;
                        }
                        catch (MySql.Data.MySqlClient.MySqlException e)
                        {
                            throw e;
                        }
                    }
                }
            }


            /// <summary>
            /// 执行多条SQL语句，实现数据库事务。
            /// </summary>
            /// <param name="SQLStringList">SQL语句的哈希表（key为sql语句，value是该语句的MySqlParameter[]）</param>
            public static void ExecuteSqlTran(Hashtable SQLStringList)
            {
                using (MySqlConnection conn = new MySqlConnection(connectionString))
                {
                    conn.Open();
                    using (MySqlTransaction trans = conn.BeginTransaction())
                    {
                        MySqlCommand cmd = new MySqlCommand();
                        try
                        {
                            //循环
                            foreach (DictionaryEntry myDE in SQLStringList)
                            {
                                string cmdText = myDE.Key.ToString();
                                MySqlParameter[] cmdParms = (MySqlParameter[])myDE.Value;
                                PrepareCommand(cmd, conn, trans, cmdText, cmdParms);
                                int val = cmd.ExecuteNonQuery();
                                cmd.Parameters.Clear();
                            }
                            trans.Commit();
                        }
                        catch
                        {
                            trans.Rollback();
                            throw;
                        }
                    }
                }
            }



            /// <summary>
            /// 执行多条SQL语句，实现数据库事务。
            /// </summary>
            /// <param name="SQLStringList">SQL语句的哈希表（key为sql语句，value是该语句的MySqlParameter[]）</param>
            public static void ExecuteSqlTranWithIndentity(Hashtable SQLStringList)
            {
                using (MySqlConnection conn = new MySqlConnection(connectionString))
                {
                    conn.Open();
                    using (MySqlTransaction trans = conn.BeginTransaction())
                    {
                        MySqlCommand cmd = new MySqlCommand();
                        try
                        {
                            int indentity = 0;
                            //循环
                            foreach (DictionaryEntry myDE in SQLStringList)
                            {
                                string cmdText = myDE.Key.ToString();
                                MySqlParameter[] cmdParms = (MySqlParameter[])myDE.Value;
                                foreach (MySqlParameter q in cmdParms)
                                {
                                    if (q.Direction == ParameterDirection.InputOutput)
                                    {
                                        q.Value = indentity;
                                    }
                                }
                                PrepareCommand(cmd, conn, trans, cmdText, cmdParms);
                                int val = cmd.ExecuteNonQuery();
                                foreach (MySqlParameter q in cmdParms)
                                {
                                    if (q.Direction == ParameterDirection.Output)
                                    {
                                        indentity = Convert.ToInt32(q.Value);
                                    }
                                }
                                cmd.Parameters.Clear();
                            }
                            trans.Commit();
                        }
                        catch
                        {
                            trans.Rollback();
                            throw;
                        }
                    }
                }
            }

            /// <summary>
            /// 执行一条计算查询结果语句，返回查询结果（object）。
            /// </summary>
            /// <param name="SQLString">计算查询结果语句</param>
            /// <returns>查询结果（object）</returns>
            public static object GetSingle(string SQLString, params MySqlParameter[] cmdParms)
            {   //建立连接
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {   //创建SQL执行命令
                    using (MySqlCommand cmd = new MySqlCommand())
                    {
                        try
                        {   //执行SQL
                            PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                            object obj = cmd.ExecuteScalar();
                            //处理返回结果
                            cmd.Parameters.Clear();
                            if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
                            {
                                return null;
                            }
                            else
                            {
                                return obj;
                            }
                        } //关闭数据库连接
                        catch (MySql.Data.MySqlClient.MySqlException e)
                        {
                            throw e;
                        }
                    }
                }
            }




            /// <summary>
            /// 执行查询语句，返回MySqlDataReader ( 注意：调用该方法后，一定要对MySqlDataReader进行Close )
            /// </summary>
            /// <param name="strSQL">查询语句</param>
            /// <returns>MySqlDataReader</returns>
            public static MySqlDataReader ExecuteReader(string SQLString, params MySqlParameter[] cmdParms)
            {
                MySqlConnection connection = new MySqlConnection(connectionString);
                MySqlCommand cmd = new MySqlCommand();
                try
                {
                    PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                    MySqlDataReader myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
                    cmd.Parameters.Clear();
                    return myReader;
                }
                catch (MySql.Data.MySqlClient.MySqlException e)
                {
                    throw e;
                }
                //            finally
                //            {
                //                cmd.Dispose();
                //                connection.Close();
                //            }    

            }





            /// <summary>
            /// 执行查询语句，返回DataSet
            /// </summary>
            /// <param name="SQLString">查询语句</param>
            /// <returns>DataSet</returns>
            public static DataSet Query(string SQLString, params MySqlParameter[] cmdParms)
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    MySqlCommand cmd = new MySqlCommand();
                    PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                    using (MySqlDataAdapter da = new MySqlDataAdapter(cmd))
                    {
                        DataSet ds = new DataSet();
                        try
                        {
                            da.Fill(ds, "ds");// "ds" 表名
                            cmd.Parameters.Clear();
                        }
                        catch (MySql.Data.MySqlClient.MySqlException ex)
                        {
                            throw new Exception(ex.Message);
                        }
                        return ds;
                    }
                }
            }

            /// <summary>
            /// 执行查询语句，返回DataTable
            /// </summary>
            /// <param name="SQLString">查询语句</param>
            /// <returns>DataSet</returns>
            public static DataTable QueryTable(string SQLString, params MySqlParameter[] cmdParms)
            {
                using (MySqlConnection connection = new MySqlConnection(connectionString))
                {
                    MySqlCommand cmd = new MySqlCommand();
                    PrepareCommand(cmd, connection, null, SQLString, cmdParms);
                    using (MySqlDataAdapter da = new MySqlDataAdapter(cmd))
                    {
                        DataTable ds = new DataTable();
                        try
                        {
                            da.Fill(ds);
                            cmd.Parameters.Clear();
                        }
                        catch (MySql.Data.MySqlClient.MySqlException ex)
                        {
                            throw new Exception(ex.Message);
                        }
                        return ds;
                    }
                }
            }
        /// <summary>
        /// 预编译SQL
        /// </summary>
        /// <param name="cmd">SQL执行对象</param>
        /// <param name="conn">数据库连接</param>
        /// <param name="trans">事务处理</param>
        /// <param name="cmdText">sql语句</param>
        /// <param name="cmdParms">参数</param>
        private static void PrepareCommand(MySqlCommand cmd, MySqlConnection conn, MySqlTransaction trans, string cmdText, MySqlParameter[] cmdParms)
            {
                if (conn.State != ConnectionState.Open)
                    conn.Open();
                cmd.Connection = conn;
                cmd.CommandText = cmdText;
                if (trans != null)
                    cmd.Transaction = trans;
                cmd.CommandType = CommandType.Text;//cmdType SQL类型 TEXT正常SQL StoredProcedure存储过程，TableDirect表;
            if (cmdParms != null)
                {


                    foreach (MySqlParameter parameter in cmdParms)
                    {
                        if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) &&
                            (parameter.Value == null))
                        {
                            parameter.Value = DBNull.Value;
                        }
                        cmd.Parameters.Add(parameter);
                    }
                }
            }

        #endregion

        public static List<T> DataTableToList<T>(DataTable dt)
        {
            List<T> listT = new List<T>();

            Type type = typeof(T);//1.反射

            if (dt == null)
            {
                return listT;//防空指针异常
            }
            if (dt.Rows.Count > 0)
            {
                for (int i = 0; i < dt.Rows.Count; i++)
                {
                    T entity = Activator.CreateInstance<T>();//创建对象

                    DataRow row = dt.Rows[i];

                    PropertyInfo[] pArray = type.GetProperties();//2.得到属性

                    foreach (PropertyInfo p in pArray)
                    {
                        if (!dt.Columns.Contains(p.Name) || row[p.Name] == null || row[p.Name] == DBNull.Value)
                        {
                            continue;
                        }

                        if (p.PropertyType == typeof(DateTime) && Convert.ToDateTime(row[p.Name]) < Convert.ToDateTime("1753-01-02"))
                        {
                            continue;
                        }
                        try
                        {
                            //3.取dataTable中的记录映射到实体对象中（列名与属性名相同）
                            var obj = Convert.ChangeType(row[p.Name], p.PropertyType);
                            p.SetValue(entity, obj, null);
                        }
                        catch (Exception)
                        {
                            // throw;
                        }
                    }
                    listT.Add(entity);

                }
            }
            return listT;
        }

        public static MySqlConnection GetConnection(string connectionString)
        {
            MySqlConnection Connection = new MySqlConnection(connectionString);
            return Connection;
        }

    }

    }



